I am practicing in Bangalore, and can help you in the matter. However there cannot be a Sole Proprietor company. Company means either a Private Limited Company or a Public Limited Company.
As you are starter, you can go for Pvt. Limited Company with one lakh capital. It costs you approximately 25000/- to float a company with a share capital of Rs.lakh.if you have Digital signature or else the cost for digital signature and DIN no. is extra. It is inclusive of all professional charges and compliance for one year.
Registration under service tax is free, there is fee for the registration payable to government, you only have to file an appliacation. with a pan no.
In case you need my services call on Mobile 9241780775 M.G.Kotresh